Allogeneic peripheral blood stem cell transplantation using reduced intensity versus myeloablative conditioning regimens for the treatment of leukemia.

Reduced intensity conditioning (RIC) have allowed the application of transplantation to older patients and to patients with underlying medical problems. Between October, 1999, and June, 2003, 61 patients with acute leukemia or chronic myeloid leukemia received allogeneic peripheral blood hematopoietic stem cell transplantation (HSCT) from HLA-identical siblings. Thirty-four were conditioned with myeloablative protocols and twenty-seven with RIC regimens. The patients in the myeloablative group were younger (29 vs. 37 years; p < 0.0003), most of them were transplanted in complete remission (74% vs. 59%; p < 0.03), had a shorter interval between diagnosis and HSCT (12 vs. 21 months; p < 0.02) and a greater proportion belonged to standard-risk prognosis (68% vs. 48%; p < 0.1). The median times to neutrophil, platelet and red blood cell engraftment for the myeloablative and RIC groups were 14 versus 11 days (p < 0.009), 17 versus 9 days (p < 0.0001), and 19 versus 12 days (p < 0.007), respectively. Transfusion requirements were lower in the RIC group. Severe mucositis was present in 32% and 7%, respectively (p < 0.01). The proportion of patients having acute graft versus-disease (GVHD), chronic GVHD, and infections was the same, as well as early and late mortality, disease-free survival, and overall survival. Analyzing all the patients together, three factors significantly influenced overall survival: standard risk patients, complete remission at transplant, and the absence of severe acute GVHD. In conclusion, our data suggest that even in high-risk patients, RIC transplantation seems to be as useful as ablative HSCT.

IFN-alpha as induction and maintenance treatment of patients newly diagnosed with Waldenström's macroglobulinemia.

Waldenström's macroglobulinemia is a rare malignant disorder of B lymphocytes. There are no studies on the use of interferon-alpha (IFN-alpha) as frontline therapy in this disease. Between April 1991 and September 2000, we treated 21 newly diagnosed patients using 8 mg/m(2) chlorambucil and 40 mg/m(2) prednisone p.o. daily for 10 days and 3 megaU/m(2) IFN-alpha three times a week. Patients who responded after induction continued receiving IFN until relapse or death. We found a high frequency of peripheral neuropathy (43%) and grade 3 diffuse marrow fibrosis (43%). Objective response was achieved in 12 (57%) patients, including 4 (19%) complete responders. Median time from treatment to response was 8 months (range 3-18). Median progression-free survival was 70 months (95% CI 47-93), and overall survival was 91 months (95% CI 50-132). Patients who achieved objective response lived longer (91 vs. 33 months, p < 0.03), as did patients who had lactic dehydrogenase (LDH) < 180 U/L (89 vs. 54 months, p < 0.01). Grade 3 hematologic toxicity was observed during induction in 5 patients. IFN-alpha is an effective agent for the induction and maintenance treatment of Waldenström's macroglobulinemia patients. LDH > 180 U/L and failure to respond are adverse prognostic factors.